programming fundamentals and data types

A variable is a named memory location that holds data that during the execution of a program, the data can change.

A constant is fixed data that during the execution of a program cannot change.

Assignment is the process of storing data in a variable or constant under a descriptive name. E.g. name = "SME"

An operator is a symbol used to instruct a computer to perform a specific operation on one or more values. E.g. arithmetic, comparison

Arithmetic operators include:

Comparison operators include:

An input is a value that is read from an input device and then processed by a computer program.

False. Without inputs, programs are not useful as they can't interact with the outside world and always produce the same result.

An output is a value sent to an output device from a computer program.

Typical output devices include:

A programming construct determines the order in which lines of code are executed and controls the logic and behaviour of code.

The three core programming constructs are sequence, selection, and iteration.

Sequence refers to lines of code which are run one line at a time in the order they are written from first to last.

Selection is when the flow of a program is changed depending on a set of conditions, determining which lines or block of code runs next.

Two ways to write selection statements are: if...then...else statements and case/switch statements.

Iteration is repeating a line or block of code using a loop.

Iteration can be count controlled (e.g. for loop) or condition controlled (e.g. while loop).

The keywords indicating selection are if, elseif, else, endif, switch, case.

The keywords indicating iteration are for, while, do.

If no selection or iteration keywords are present, the construct is sequence.

10 MOD 3 = 1

10 DIV 3 = 3

2 ^ 3 = 8

15 % 4 = 3

10 // 2 = 5

True. A data type classifies data into groups according to the kind of data they represent.

A data type is a classification of data into groups according to the kind of data they represent.

An integer is a data type used for whole numbers like 10, -5, 0.

A real is a data type used for numbers with a fractional part like 3.14, -2.5, 0.0.

A character is a data type used for single characters like 'a', 'B', '6', '£'.

A string is a data type used for a sequence of characters like "Hello world", "ABC", "@#!%".

A Boolean is a data type used for true or false values like True, False.

Casting is when you convert one data type to another data type.

True. Casting changes the data type within a program.

real_value = float(X)

int_value = int(X)

str_value = str(X)